Satellite hunters: a brief history of anti-space fighter jets

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Through the last century, fighter aircraft evolved towards multifunctionality – an ability to engage vaster and vaster arrays of targets as long as an appropriate weapon and targeting systems are provided. From machineguns to cannons to missiles, and from calculating gunsights to radars to data links, the means of engaging those targets became more sophisticated and more capable.

It was only a question of time before this progression reached the next logical step: blowing up things in space.

In theory, destroying satellites is not that much more difficult than deploying them. If one has a rocket capable of putting an item into orbit, it does not matter what that item is – a satellite or a bit of explosives aimed at a satellite. 

Furthermore, the whole idea of staying in orbit means traveling incredibly fast – for most satellites, orbital speeds reach 28,000 kilometers (17,000 miles) per hour. To intercept a satellite and blow it up you don’t need to do that; you only have to reach the same altitude it is going to pass, and preferably – be at the same spot at the same time.

The trick, of course, lies in putting the two together. A satellite is a small object in an incredible vastness of space. Although it usually moves in a rather predictable orbital trajectory, tracking it, calculating its path, and putting a missile in close proximity of it requires no small feat of engineering and mathematics.

The appeal of the air launch

The most obvious candidate for such an interception is, obviously, a ballistic missile: a platform designed to reach space and fall down. It is relatively cheap and easy to launch, and with the ability to put it into a trajectory that intersects the satellite’s path at some point, we have ourselves a satellite killer.

No wonder the majority of anti-satellite weapons developed throughout history were modified ballistic missiles. Both the United States and the Soviet Union experimented with them; China and India tested theirs in the 21st century. Such a system seems easy to acquire and convenient to use.

But then there is the whole conventional launch vs air launch debate. Any rocket, before it goes into space, has to travel through Earth’s atmosphere. Why not put it halfway there in advance? Launching rockets from high-flying aircraft rather than from the surface means saving on fuel and infrastructure, being independent of weather, and in general, having a lot more flexibility and secrecy. Some commercial space companies are doing that, but the idea did not really stick with civilian space programs; militaries, on the other hand, are dabbling with it to this day.

The flexibility is vastly more beneficial if we are talking about the conditions that are likely to be encountered in a war. A military could suddenly find itself in a dire need to take down the enemy’s satellite without committing to something that could be interpreted as a beginning of a ballistic nuclear strike. An interception mission could be masked as a routine patrol of a bomber or a fighter jet, and the enemy would be unalerted before it is too late.

Nuking the orbit

The flexibility and secrecy of air launch apply to ballistic missiles too. Having understood that, in the 50s the US launched the development of the Bold Orion and the High Virgo: ballistic missiles intended to be launched by strategic bombers, the Boeing B-47 Stratojet and the Convair B-58 Hustler respectively. Both had anti-satellite variants and both performed tests in 1959.

The High Virgo test was unsuccessful and the program got discontinued. The Bold Orion passed within 6 kilometers (4 miles) of its target satellite, which would have been enough to destroy it had the missile been armed with a nuclear warhead.

With the precision of early ballistic missiles being calculated in kilometers, the only way to shoot down a satellite was to obliterate as large a chunk of low earth orbit as possible. But that was also the time when nuclear devices were intended to be crammed into every conceivable platform, from howitzers to family sedans. So, shooting down satellites with nuclear bombs seemed like a way forward.

High-altitude nuclear tests of the late 50s and early 60s convinced the military otherwise. Such explosions resulted in the electromagnetic pulse (EMP) frying electronics and disrupting radio communication in a large part of the globe, and it was nearly impossible to take down enemy satellites without destroying your own. It was not a particularly elegant solution, so, air launched satellite killers went away.  

High-precision tin cans

Through the 60s and the 70s, both the US and the Soviet Union poured money into various kinds of anti-orbit weapons, mostly based on conventionally launched ballistic missiles as well as lasers. The Soviets were a bit too successful at that for the US’ liking. So, in 1978 the US launched a program to develop an all-new kind of satellite hunter: cheap, flexible, and secretive.

The McDonnell Douglas F-15 Eagle fighter jet, which has entered service in 1976, had a payload capacity on par with strategic bombers from the 50s, as well as speed and service ceiling that significantly outmatched them. 

By that time the satellite tracking technology also improved, as did the precision of guided missiles. It seemed possible to destroy satellites with something as small as an air-to-air missile, and Ling-Temco-Vought conglomerate took the challenge.

They strapped together components of two nuclear missiles to act as rocket stages, put an infrared homing sensor on top, and called it the ASM-135. The warhead contained no explosives and relied on the force of the collision, which should have been enough to smash the satellite into pieces. 

The press dubbed the weapon “a flying tomato can”. In September 1985, an F-15A fighter jet, named Celestial Eagle, took off from Vandenberg air base, zoom-climbed to 11.6 kilometers (38,100 feet), and sent the can right into a malfunctioning solar observation satellite. The target disintegrated, scattering pieces that remained in the orbit for almost two decades.

The Soviets did not like what they saw and protested heavily. But at the same time, they had their own counterpart brewing, the 79M6 Kontakt – a project remarkably similar to the ASM-135. It was a three-stage rocket with a kinetic warhead and used the MiG-31 Foxhound heavy interceptor as a platform.

Being heavier and having a longer range than the American missile, the Kontakt was, from the onset, intended to be mass-produced and employed en masse. It had to disable the US’ reconnaissance and communication satellite network at the first moments of the Cold War turning hot. If it was not for the Soviet Union’s collapse, we would have likely seen it employed.

The space apocalypse

As the time came for the Kontakt to be tested, the Soviet Union was in pieces. The project was discontinued, and although various components of Foxhound’s anti-satellite missile were complete, it never had an operational prototype. 

The ASM-135 disappeared even before that. To say that the project was problematic would be an understatement. While simple in concept, in its execution the weapon was incredibly complex and expensive. It required a special fighter jet with modified targeting systems and a whole package of ground infrastructure. 

Another problem was even more severe. The thing is, if you put something in orbit, it really, really wants to stay there. Destroying a satellite results in a massive spread of debris that resembles a shotgun blast – a field of small pieces that continue to fly in the same orbit and are tens of times faster than bullets. The field spreads, impacts other satellites, and creates even more debris. 

Such a cascade, called the Kessler effect, could wipe out the entire low earth orbit in a matter of days. The pieces of thousands of mangled satellites would remain there for decades if not for centuries, bringing any kind of space exploration to a complete halt. Satellite-based navigation and communication would become a thing of the past too.

So far, humanity has been somewhat lucky – none of the successful anti-satellite weapon tests resulted in the cascade, although some events came dangerously close. Yet, any form of active space warfare would likely end up in exactly this scenario.

The US curbed its development of anti-satellite weaponry and killed the ASM-135, although that was mostly a result of its massive cost. Russia had no means to continue the development of the Kontakt, and the problem sorted itself out. 

China and India have conducted widely-condemned anti-satellite tests since then, using modified ballistic missiles. Similar platforms remained in use by the US and Russia as well, but fighter jets were no longer a part of these efforts.

The comeback

The situation remained unchanged until 2018. On the wave of rising international tensions, Russian president Vladimir Putin announced a whole package of Russia’s newest cutting-edge weaponry, including hypersonic and nuclear missiles.

This wave of modernization included the Kh-47M2 Kinzhal air-launched ballistic missile, used by the same MiG-31. Reportedly, the Kinzhal borrowed heavily from the Kontakt, although that is most likely untrue – the weapon traces its origins to another ballistic missile, the Iskander. 

The Kinzhal has already reached initial operational capability. Russia is rather ambiguous of whether or not it is intended to be an anti-satellite weapon, but there is no doubt that in theory it can fulfill that role. Also, if all the reports are true, Russia has a good half-a-dozen of other anti-satellite missiles in development and at least some of them could very well be intended for aerial launch.

The US has not followed up on the ASM-135 though. So, the MiG-31 remains the only operational anti-space fighter jet, at least in theory.

In practice, the F-15A Celestial Eagle remains the only jet to ever achieve air-to-space kill. The aircraft itself, for several past decades, remained in flyable condition at Homestead Air Reserve Base, although it most likely no longer has all the hardware necessary for lobbing tomato cans at spacecraft.

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